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1.
Circ Res ; 133(6): 508-531, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37589160

RESUMO

BACKGROUND: Hypoxia is a major cause and promoter of pulmonary hypertension (PH), a representative vascular remodeling disease with poor prognosis and high mortality. However, the mechanism underlying how pulmonary arterial system responds to hypoxic stress during PH remains unclear. Endothelial mitochondria are considered signaling organelles on oxygen tension. Results from previous clinical research and our studies suggested a potential role of posttranslational SUMOylation (small ubiquitin-like modifier modification) in endothelial mitochondria in hypoxia-related vasculopathy. METHODS: Chronic hypoxia mouse model and Sugen/hypoxia rat model were employed as PH animal models. Mitochondrial morphology and subcellular structure were determined by transmission electron and immunofluorescent microscopies. Mitochondrial metabolism was determined by mitochondrial oxygen consumption rate and extracellular acidification rate. SUMOylation and protein interaction were determined by immunoprecipitation. RESULTS: The involvement of SENP1 (sentrin-specific protease 1)-mediated SUMOylation in mitochondrial remodeling in the pulmonary endothelium was identified in clinical specimens of hypoxia-related PH and was verified in human pulmonary artery endothelial cells under hypoxia. Further analyses in clinical specimens, hypoxic rat and mouse PH models, and human pulmonary artery endothelial cells and human embryonic stem cell-derived endothelial cells revealed that short-term hypoxia-induced SENP1 translocation to endothelial mitochondria to regulate deSUMOylation (the reversible process of SUMOylation) of mitochondrial fission protein FIS1 (mitochondrial fission 1), which facilitated FIS1 assembling with fusion protein MFN2 (mitofusin 2) and mitochondrial gatekeeper VDAC1 (voltage-dependent anion channel 1), and the membrane tethering activity of MFN2 by enhancing its oligomerization. Consequently, FIS1 deSUMOylation maintained the mitochondrial integrity and endoplasmic reticulum-mitochondria calcium communication across mitochondrial-associated membranes, subsequently preserving pulmonary endothelial function and vascular homeostasis. In contrast, prolonged hypoxia disabled the FIS1 deSUMOylation by diminishing the availability of SENP1 in mitochondria via inducing miR (micro RNA)-138 and consequently resulted in mitochondrial dysfunction and metabolic reprogramming in pulmonary endothelium. Functionally, introduction of viral-packaged deSUMOylated FIS1 within pulmonary endothelium in mice improved pulmonary endothelial dysfunction and hypoxic PH development, while knock-in of SUMO (small ubiquitin-like modifier)-conjugated FIS1 in mice exaggerated the diseased cellular and tissue phenotypes. CONCLUSIONS: By maintaining endothelial mitochondrial homeostasis, deSUMOylation of FIS1 adaptively preserves pulmonary endothelial function against hypoxic stress and consequently protects against PH. The FIS1 deSUMOylation-SUMOylation transition in pulmonary endothelium is an intrinsic pathogenesis of hypoxic PH.


Assuntos
Hipertensão Pulmonar , Doenças Vasculares , Humanos , Camundongos , Ratos , Animais , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/prevenção & controle , Células Endoteliais , Mitocôndrias , Modelos Animais de Doenças , Endotélio , Ubiquitinas , Proteínas de Membrana , Proteínas Mitocondriais
2.
Virol J ; 21(1): 110, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745209

RESUMO

BACKGROUND: Severe pneumonia is one of the most important causes of mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Adenovirus (ADV) is a significant cause of severe viral pneumonia after allo-HSCT, and we aimed to identify the clinical manifestations, prognostic factors, and outcomes of ADV pneumonia after allo-HSCT. METHODS: Twenty-nine patients who underwent allo-HSCT at the Peking University Institute of Hematology and who experienced ADV pneumonia after allo-HSCT were enrolled in this study. The Kaplan-Meier method was used to estimate the probability of overall survival (OS). Potential prognostic factors for 100-day OS after ADV pneumonia were evaluated through univariate and multivariate Cox regression analyses. RESULTS: The incidence rate of ADV pneumonia after allo-HSCT was approximately 0.71%. The median time from allo-HSCT to the occurrence of ADV pneumonia was 99 days (range 17-609 days). The most common clinical manifestations were fever (86.2%), cough (34.5%) and dyspnea (31.0%). The 100-day probabilities of ADV-related mortality and OS were 40.4% (95% CI 21.1%-59.7%) and 40.5% (95% CI 25.2%-64.9%), respectively. Patients with low-level ADV DNAemia had lower ADV-related mortality and better OS than did those with high-level (≥ 106 copies/ml in plasma) ADV DNAemia. According to the multivariate analysis, high-level ADV DNAemia was the only risk factor for intensive care unit admission, invasive mechanical ventilation, ADV-related mortality, and OS after ADV pneumonia. CONCLUSIONS: We first reported the prognostic factors and confirmed the poor outcomes of patients with ADV pneumonia after allo-HSCT. Patients with high-level ADV DNAemia should receive immediate and intensive therapy.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Pneumonia Viral , Transplante Homólogo , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Prognóstico , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Adulto Jovem , Adolescente , Transplante Homólogo/efeitos adversos , Infecções por Adenoviridae/mortalidade , Fatores de Risco , Estudos Retrospectivos , Adenoviridae , Resultado do Tratamento , Incidência , Infecções por Adenovirus Humanos/mortalidade , Infecções por Adenovirus Humanos/virologia
3.
Gut ; 72(8): 1568-1580, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36450387

RESUMO

OBJECTIVE: Immune checkpoint blockade (ICB) has improved cancer treatment, yet why most hepatocellular carcinoma (HCC) patients are resistant to PD-1 ICB remains elusive. Here, we elucidated the role of a programmed cell death protein 1 (PD-1) isoform, Δ42PD-1, in HCC progression and resistance to nivolumab ICB. DESIGN: We investigated 74 HCC patients in three cohorts, including 41 untreated, 28 treated with nivolumab and 5 treated with pembrolizumab. Peripheral blood mononuclear cells from blood samples and tumour infiltrating lymphocytes from tumour tissues were isolated for immunophenotyping. The functional significance of Δ42PD-1 was explored by single-cell RNA sequencing analysis and validated by functional and mechanistic studies. The immunotherapeutic efficacy of Δ42PD-1 monoclonal antibody was determined in HCC humanised mouse models. RESULTS: We found distinct T cell subsets, which did not express PD-1 but expressed its isoform Δ42PD-1, accounting for up to 71% of cytotoxic T lymphocytes in untreated HCC patients. Δ42PD-1+ T cells were tumour-infiltrating and correlated positively with HCC severity. Moreover, they were more exhausted than PD-1+ T cells by single T cell and functional analysis. HCC patients treated with anti-PD-1 ICB showed effective PD-1 blockade but increased frequencies of Δ42PD-1+ T cells over time especially in patients with progressive disease. Tumour-infiltrated Δ42PD-1+ T cells likely sustained HCC through toll-like receptors-4-signalling for tumourigenesis. Anti-Δ42PD-1 antibody, but not nivolumab, inhibited tumour growth in three murine HCC models. CONCLUSION: Our findings not only revealed a mechanism underlying resistance to PD-1 ICB but also identified anti-Δ42PD-1 antibody for HCC immunotherapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Leucócitos Mononucleares , Terapia de Imunossupressão , Tolerância Imunológica , Imunoterapia , Nivolumabe/uso terapêutico , Linfócitos T CD8-Positivos
4.
Hum Reprod ; 37(7): 1664-1677, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35526155

RESUMO

STUDY QUESTION: Do variants in helicase for meiosis 1 (HFM1) account for male infertility in humans? SUMMARY ANSWER: Biallelic variants in HFM1 cause human male infertility owing to non-obstructive azoospermia (NOA) with impaired crossover formation and meiotic metaphase I (MMI) arrest. WHAT IS KNOWN ALREADY: HFM1 encodes an evolutionarily conserved DNA helicase that is essential for crossover formation and completion of meiosis. The null mutants of Hfm1 or its ortholog in multiple organisms displayed spermatogenic arrest at the MMI owing to deficiencies in synapsis and severe defects in crossover formation. Although HFM1 variants were found in infertile men with azoospermia or oligozoospermia, the causal relationship has not yet been established with functional evidence. STUDY DESIGN, SIZE, DURATION: A Pakistani family, having two infertile brothers born to consanguineous parents, and three unrelated Chinese men diagnosed with NOA were recruited for pathogenic variants screening. PARTICIPANTS/MATERIALS, SETTING, METHODS: All the patients were diagnosed with idiopathic NOA and, for the Chinese patients, meiotic defects were confirmed by histological analyses and/or immunofluorescence staining on testicular sections. Exome sequencing and subsequent bioinformatic analyses were performed to screen for candidate pathogenic variants. The pathogenicity of identified variants was assessed and studied in vivo in mice carrying the equivalent mutations. MAIN RESULTS AND THE ROLE OF CHANCE: Six variants (homozygous or compound heterozygous) in HFM1 were identified in the three Chinese patients with NOA and two brothers with NOA from the Pakistani family. Testicular histological analysis revealed that spermatogenesis is arrested at MMI in patients carrying the variants. Mice modeling the HFM1 variants identified in patients recapitulated the meiotic defects of patients, confirming the pathogenicity of the identified variants. These Hfm1 variants led to various reductions of HFM1 foci on chromosome axes and resulted in varying degrees of synapsis and crossover formation defects in the mutant male mice. In addition, Hfm1 mutant female mice displayed infertility or subfertility with oogenesis variously affected. LIMITATIONS, REASONS FOR CAUTION: A limitation of the current study is the small sample size. Owing to the unavailability of fresh testicular samples, the defects of synapsis and crossover formation could not be detected in spermatocytes of patients. Owing to the unavailability of antibodies, we could not quantify the impact of these variants on HFM1 protein levels. WIDER IMPLICATIONS OF THE FINDINGS: Our findings provide direct clinical and in vivo functional evidence that HFM1 variants cause male infertility in humans and also suggest that HFM1 may regulate meiotic crossover formation in a dose-dependent manner. Noticeably, our findings from mouse models showed that HFM1 variants could impair spermatogenesis and oogenesis with a varying degree of severity and might also be compatible with the production of a few spermatozoa in men and subfertility in women, extending the phenotypic spectrum of patients with HFM1 variants. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China (31890780, 32070850, 32061143006, 32000587 and 31900398) and the Fundamental Research Funds for the Central Universities (YD2070002007 and YD2070002012). The authors declare no potential conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Azoospermia , Infertilidade Masculina , Animais , Azoospermia/patologia , DNA Helicases/genética , DNA Helicases/metabolismo , Feminino , Humanos , Infertilidade Masculina/diagnóstico , Masculino , Camundongos , Espermatogênese/genética , Espermatozoides/metabolismo , Testículo/metabolismo
5.
BMC Med Genet ; 21(1): 134, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32560637

RESUMO

BACKGROUND: Liver cancer is one of the most common cancers in the world. The primary aim of this research was to discover the correlation between single nucleotide polymorphisms (SNPs) of the MIR155HG and liver cancer risk. METHODS: The selected SNPs in MIR155HG were genotyped utilizing the Agena MassARRAY platform. We evaluated the correlation between MIR155HG polymorphisms and Liver cancer by genetic model analysis, stratification analysis and haplotype analysis. Relative risk of Liver cancer was shown based on odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS: Our results uncovered that rs12482371 and rs1893650 in the MIR155HG were associated with protection against Liver cancer. And the rs928883 was related to increase risk of Liver cancer. Furthermore, apart from rs77218221, other selected SNPs formed two LD blocks, and haplotype "GATAG" in block 2 elevated individual liver cancer risk. CONCLUSIONS: MIR155HG gene polymorphism may be correlated to Liver cancer susceptibility in Han Chinese population, particularly in males and aged ≤55 years.


Assuntos
Povo Asiático/genética , Etnicidade/genética , Predisposição Genética para Doença , Neoplasias Hepáticas/genética , Polimorfismo de Nucleotídeo Único/genética , RNA Longo não Codificante/genética , Fatores Etários , Estudos de Casos e Controles , Feminino , Haplótipos/genética , Humanos , Desequilíbrio de Ligação/genética , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais
6.
Circ Res ; 121(6): 636-649, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28760777

RESUMO

RATIONALE: The highly conserved NOTCH (neurogenic locus notch homolog protein) signaling pathway functions as a key cell-cell interaction mechanism controlling cell fate and tissue patterning, whereas its dysregulation is implicated in a variety of developmental disorders and cancers. The pivotal role of endothelial NOTCH in regulation of angiogenesis is widely appreciated; however, little is known about what controls its signal transduction. Our previous study indicated the potential role of post-translational SUMO (small ubiquitin-like modifier) modification (SUMOylation) in vascular disorders. OBJECTIVE: The aim of this study was to investigate the role of SUMOylation in endothelial NOTCH signaling and angiogenesis. METHODS AND RESULTS: Endothelial SENP1 (sentrin-specific protease 1) deletion, in newly generated endothelial SENP1 (the major protease of the SUMO system)-deficient mice, significantly delayed retinal vascularization by maintaining prolonged NOTCH1 signaling, as confirmed in cultured endothelial cells. An in vitro SUMOylation assay and immunoprecipitation revealed that when SENP1 associated with N1ICD (NOTCH1 intracellular domain), it functions as a deSUMOylase of N1ICD SUMOylation on conserved lysines. Immunoblot and immunoprecipitation analyses and dual-luciferase assays of natural and SUMO-conjugated/nonconjugated NOTCH1 forms demonstrated that SUMO conjugation facilitated NOTCH1 cleavage. This released N1ICD from the membrane and stabilized it for translocation to the nucleus where it functions as a cotranscriptional factor. Functionally, SENP1-mediated NOTCH1 deSUMOylation was required for NOTCH signal activation in response to DLL4 (Delta-like 4) stimulation. This in turn suppressed VEGF (vascular endothelial growth factor) receptor signaling and angiogenesis, as evidenced by immunoblotted signaling molecules and in vitro angiogenesis assays. CONCLUSIONS: These results establish reversible NOTCH1 SUMOylation as a regulatory mechanism in coordinating endothelial angiogenic signaling; SENP1 acts as a critical intrinsic mediator of this process. These findings may apply to NOTCH-regulated biological events in nonvascular tissues and provide a novel therapeutic strategy for vascular diseases and tumors.


Assuntos
Células Endoteliais da Veia Umbilical Humana/metabolismo , Neovascularização Fisiológica , Receptores Notch/metabolismo , Sumoilação , Proteínas Adaptadoras de Transdução de Sinal , Animais , Sítios de Ligação , Proteínas de Ligação ao Cálcio , Células Cultivadas , Cisteína Endopeptidases , Endopeptidases/genética , Endopeptidases/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Ligação Proteica , Receptores Notch/química , Receptores de Fatores de Crescimento do Endotélio Vascular/genética , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Transdução de Sinais
7.
BMC Genomics ; 19(1): 235, 2018 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618324

RESUMO

BACKGROUND: Epilithic sister genera Oresitrophe and Mukdenia (Saxifragaceae) have an epilithic habitat (rocky slopes) and a parapatric distribution in East Asia, which makes them an ideal model for a more comprehensive understanding of the demographic and divergence history and the influence of climate changes in East Asia. However, the genetic background and resources for these two genera are scarce. RESULTS: The complete chloroplast (cp) genomes of two Oresitrophe rupifraga and one Mukdenia rossii individuals were reconstructed and comparative analyses were conducted to examine the evolutionary pattern of chloroplast genomes in Saxifragaceae. The cp genomes ranged from 156,738 bp to 156,960 bp in length and had a typical quadripartite structure with a conserved genome arrangement. Comparative analysis revealed the intron of rpl2 has been lost in Heuchera parviflora, Tiarella polyphylla, M. rossii and O. rupifraga but presents in the reference genome of Penthorum chinense. Seven cp hotspot regions (trnH-psbA, trnR-atpA, atpI-rps2, rps2-rpoC2, petN-psbM, rps4-trnT and rpl33-rps18) were identified between Oresitrophe and Mukdenia, while four hotspots (trnQ-psbK, trnR-atpA, trnS-psbZ and rpl33-rps18) were identified within Oresitrophe. In addition, 24 polymorphic cpSSR loci were found between Oresitrophe and Mukdenia. Most importantly, we successfully developed 126 intergeneric polymorphic gSSR markers between Oresitrophe and Mukdenia, as well as 452 intrageneric ones within Oresitrophe. Twelve randomly selected intergeneric gSSRs have shown that these two genera exhibit a significant genetic structure. CONCLUSIONS: In this study, we conducted genome skimming for Oresitrophe rupifraga and Mukdenia rossii. Using these data, we were able to not only assemble their complete chloroplast genomes, but also develop abundant genetic resources (cp hotspots, cpSSRs, polymorphic gSSRs). The genomic patterns and genetic resources presented here will contribute to further studies on population genetics, phylogeny and conservation biology in Saxifragaceae.


Assuntos
Genoma de Cloroplastos , Proteínas de Plantas/genética , Saxifragaceae/genética , Análise de Sequência de DNA/métodos , Ecossistema , Evolução Molecular , Marcadores Genéticos , Genética Populacional , Genoma de Planta , Filogenia , Saxifragaceae/classificação
8.
Cell Immunol ; 302: 50-57, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26861148

RESUMO

Osteoarthritis (OA) is characterized by articular cartilage degradation and joint inflammation. MicroRNAs have been proven to play an important role in the regulation of chondrogenesis. The aim of the present study was to investigate the effect of miR-502-5p in OA. The results showed that miR-502-5p levels were significantly down-regulated in OA articular tissues and IL-1ß-induced chondrocytes compared with control groups. MiR-502-5p overexpression inhibited IL-1ß-induced reduction in cell viability and increase in cell apoptosis, and alleviated IL-1ß-induced extracellular matrix (ECM) metabolic imbalance and pro-inflammatory cytokine production. MiR-502-5p targeted the 3'-untranslated region (UTR) of TRAF2 to inhibit its expression. The IL-1ß-induced activation of NF-κB signaling pathway was inhibited by PDTC, an inhibitor of NF-κB, which was also suppressed by the miR-502-5p mimic and TRAF2 siRNA transfection. In conclusion, miR-502-5p may exhibit a protective effect on IL-1ß-induced chondrocyte injury by targeting TRAF2 and inhibiting NF-κB signaling pathway.


Assuntos
Condrócitos/metabolismo , MicroRNAs/metabolismo , Osteoartrite/fisiopatologia , Fator 2 Associado a Receptor de TNF/metabolismo , Sobrevivência Celular/genética , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Regulação para Baixo , Ativação Enzimática , Humanos , Interleucina-1beta/toxicidade , MicroRNAs/genética , NF-kappa B/metabolismo , Osteoartrite/imunologia , Transdução de Sinais , Fator 2 Associado a Receptor de TNF/genética
9.
Sci Rep ; 13(1): 8187, 2023 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-37210457

RESUMO

Morphological parameters of knee joint are related to race and nationality. At present, knee prosthesis come from white male population. Due to the mismatch between the prosthesis and other ethnic groups, the prosthesis life span is reduced, revision surgery and the patients' economic burden are increased. There is no data of the Mongolian ethnic group. In order to treat patients more accurately, we measured the Mongolian data of the femoral condyle. A total of 122 knee joints were scanned in 61 volunteers (21 males and 40 females) with an average age of 23.259 ± 1.395 years. The Mimics software was used to reconstruct the 3D image and measure the data of each line. The data were analyzed by statistical methods such as t test, and P < 0.05 was taken as the significant. 122 normal femoral condyle data were obtained. The mean transverse diameter of femoral condyle is 76.472 ± 5.952 mm, medial condyle is 29.259 ± 11.461 mm, and the sagittal diameter of the medial condyle was 56.758 ± 4.163 mm. The transverse diameter of the lateral femoral condyle is 29.388 ± 3.157 mm, the sagittal diameter of the lateral condyle is 58.937 ± 3.527 mm and the femoral plane rate is 1.264 ± 0.072. (1) There was no statistical significance in the left and right knee joint data (P > 0.05). (2) The different genders data of femoral condyle were statistically significant (P < 0.05). (3) Compared with other nationalities and races, the data of femoral condyle are different. (4) There are differences between femoral surface ratio and mainstream prosthesis data.


Assuntos
Artroplastia do Joelho , Relevância Clínica , Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Articulação do Joelho/cirurgia , Fêmur/cirurgia , Artroplastia do Joelho/métodos , Epífises/cirurgia
10.
Int J Lab Hematol ; 45(1): 72-81, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36193870

RESUMO

INTRODUCTION: A higher CD34+ cell dose in allografts is associated with faster haematopoietic recovery after allogeneic haematopoietic stem cell transplantation (allo-HSCT). Leukaemia stem cells impair normal bone marrow (BM) niches and induce BM failure during leukemogenesis. However, whether measurable residual disease (MRD), known as the persistence of low-level leukaemic cells, could influence the effects of CD34+ cell dose on haematopoietic recovery after transplantation in acute lymphoblastic leukaemia (ALL) patients is unknown. METHODS: A total of 975 ALL patients were enrolled and classified into pre-HSCT MRD-positive and MRD-negative subgroups. Cox proportional hazard regression models were built for time-to-event outcomes. Multivariate analysis was performed to determine independent influencing factors from the univariate analysis. RESULTS: An appropriate CD34+ cell dose was positively associated with faster haematopoietic recovery in the total ALL population. More importantly, in pre-HSCT MRD-positive ALL patients, a higher CD34+ cell dose (≥2.76 × 106 /kg) was related to faster neutrophil (HR 1.330, 95% CI 1.045-1.692, p = 0.021) and platelet engraftment (HR 1.808, 95% CI 1.412-2.316, p < 0.001) in multivariate analysis. CD34+ cell dose was a crucial factor associated with either engraftment or transplant outcomes, although we did not demonstrate direct correlations of CD34+ cell dose with relapse, TRM, LFS or OS after allo-HSCT. CONCLUSION: Our results indicated that no additional CD34+ stem and progenitor cell harvests were needed to ensure successful haematopoietic recovery in pre-HSCT MRD-positive patients compared to pre-HSCT MRD-negative patients.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Recidiva Local de Neoplasia , Transplante de Células-Tronco Hematopoéticas/métodos , Transplante Homólogo , Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia
11.
Cell Discov ; 9(1): 88, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37612290

RESUMO

During meiosis, at least one crossover must occur per homologous chromosome pair to ensure normal progression of meiotic division and accurate chromosome segregation. However, the mechanism of crossover formation is not fully understood. Here, we report a novel recombination protein, C12ORF40/REDIC1, essential for meiotic crossover formation in mammals. A homozygous frameshift mutation in C12orf40 (c.232_233insTT, p.Met78Ilefs*2) was identified in two infertile men with meiotic arrest. Spread mouse spermatocyte fluorescence immunostaining showed that REDIC1 forms discrete foci between the paired regions of homologous chromosomes depending on strand invasion and colocalizes with MSH4 and later with MLH1 at the crossover sites. Redic1 knock-in (KI) mice homozygous for mutation c.232_233insTT are infertile in both sexes due to insufficient crossovers and consequent meiotic arrest, which is also observed in our patients. The foci of MSH4 and TEX11, markers of recombination intermediates, are significantly reduced numerically in the spermatocytes of Redic1 KI mice. More importantly, our biochemical results show that the N-terminus of REDIC1 binds branched DNAs present in recombination intermediates, while the identified mutation impairs this interaction. Thus, our findings reveal a crucial role for C12ORF40/REDIC1 in meiotic crossover formation by stabilizing the recombination intermediates, providing prospective molecular targets for the clinical diagnosis and therapy of infertility.

12.
Biochem Genet ; 50(11-12): 967-77, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22983686

RESUMO

The study of polymorphism of the UGT1A1 gene has not been reported in the Chinese Tibetan population, and there are no comparisons of genetic polymorphism in the gene between Chinese Han and Tibetan populations. In this study, we directly sequenced the functional regions of the UGT1A1 gene in 200 unrelated healthy Chinese volunteers, detecting 20 variations (including five novel ones). The distributions of allele and genotype frequencies differ between the two groups. UGT1A1*6 is the major reduced functional variant in the populations, and the *27 allele was detected only in the Han group. Differences in the frequencies of the UGT1A1*6/*63 genotype between the Tibetan and Han populations were statistically significant (P = 0.009). Our genetic data might provide fundamental information for the advance of personalized medicine and will facilitate genotype-phenotype studies in larger populations.


Assuntos
Povo Asiático/genética , Genética Populacional/métodos , Glucuronosiltransferase/genética , Polimorfismo Genético , Grupos Populacionais/genética , Regiões 5' não Traduzidas , Adolescente , Adulto , Alelos , Feminino , Frequência do Gene , Estudos de Associação Genética/métodos , Genoma Humano , Técnicas de Genotipagem , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Tibet , Adulto Jovem
13.
Oncol Ther ; 10(1): 85-103, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35103936

RESUMO

Multiple myeloma (MM) remains incurable due to relapse, although the use of proteasome inhibitors, immunomodulatory drugs, CD38-targeting antibodies, and autologous stem cell transplantation (auto-SCT) significantly improve the clinical outcomes of patients with newly diagnosed MM. In recent years, the introduction of chimeric antigen receptor T-cell (CAR T-cell) therapy has brought hope to patients with refractory and relapsed MM. The graft-versus-myeloma effect of allogeneic SCT provides the possibility for curing a subset of MM patients. In this review, we summarize the recent advances and challenges of cellular immunotherapies for MM, focusing on auto-SCT, allogeneic SCT, and CAR T-cell approaches. We also discuss future directions, and propose a specific algorithm for cellular therapies for MM and probability of minimal residual disease-directed therapy.

15.
EBioMedicine ; 77: 103904, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35248996

RESUMO

BACKGROUND: Nearly 4 billion doses of the BNT162b2-mRNA and CoronaVac-inactivated vaccines have been administrated globally, yet different vaccine-induced immunity against SARS-CoV-2 variants of concern (VOCs) remain incompletely investigated. METHODS: We compare the immunogenicity and durability of these two vaccines among fully vaccinated Hong Kong people. FINDINGS: Standard BNT162b2 and CoronaVac vaccinations were tolerated and induced neutralizing antibody (NAb) (100% and 85.7%) and spike-specific CD4 T cell responses (96.7% and 82.1%), respectively. The geometric mean NAb IC50 and median frequencies of reactive CD4 subsets were consistently lower among CoronaVac-vaccinees than BNT162b2-vaccinees. CoronaVac did not induce measurable levels of nucleocapsid protein-specific IFN-γ+ CD4+ T or IFN-γ+ CD8+ T cells compared with unvaccinated. Against VOCs, NAb response rates and geometric mean IC50 titers against B.1.617.2 (Delta) and B.1.1.529 (Omicron) were significantly lower for CoronaVac (50%, 23.2 and 7.1%, <20) than BNT162b2 (94.1%, 131 and 58.8%, 35.0), respectively. Three months after vaccinations, NAbs to VOCs dropped near to detection limit, along with waning memory T cell responses, mainly among CoronaVac-vaccinees. INTERPRETATION: Our results indicate that vaccinees especially CoronaVac-vaccinees with significantly reduced NAbs may probably face higher risk to pandemic VOCs breakthrough infection. FUNDING: This study was supported by the Hong Kong Research Grants Council Collaborative Research Fund (C7156-20GF and C1134-20GF); the Wellcome Trust (P86433); the National Program on Key Research Project of China (Grant 2020YFC0860600, 2020YFA0707500 and 2020YFA0707504); Shenzhen Science and Technology Program (JSGG20200225151410198 and JCYJ20210324131610027); HKU Development Fund and LKS Faculty of Medicine Matching Fund to AIDS Institute; Hong Kong Innovation and Technology Fund, Innovation and Technology Commission and generous donation from the Friends of Hope Education Fund. Z.C.'s team was also partly supported by the Theme-Based Research Scheme (T11-706/18-N).


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacina BNT162 , Linfócitos T CD8-Positivos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Hong Kong/epidemiologia , Humanos , Imunidade , SARS-CoV-2/genética , Vacinação
16.
Cancer Res ; 82(22): 4206-4218, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36112065

RESUMO

Patients with hepatocellular carcinoma (HCC) confront a high incidence of tumor recurrence after curative surgical resection. Hepatic ischemia-reperfusion injury (IRI) is the major consequence of surgical stress during hepatectomy. Although it has been suggested that hepatic IRI-induced immunosuppression could contribute to tumor relapse after surgery, the underlying mechanisms have not been fully defined. Here, using a multiplex cytokine array, we found that levels of postoperative IFNα serve as an independent risk factor for tumor recurrence in 100 patients with HCC with curative hepatectomy. Plasmacytoid dendritic cells (pDC), the major source of IFNα, were activated after surgery and correlated with poor disease-free survival. Functionally, IFNα was responsible for mobilization of myeloid-derived suppressor cells (MDSC) following hepatic IRI. Conditioned medium from IFNα-treated hepatocytes mediated the migration of MDSCs in vitro. Mechanistically, IFNα upregulated IRF1 to promote hepatocyte expression of CX3CL1, which subsequently recruited CX3CR1+ monocytic MDSCs. Knockdown of Irf1 or Cx3cl1 in hepatocytes significantly inhibited the accumulation of monocytic MDSCs in vivo. Therapeutically, elimination of pDCs, IFNα, or CX3CR1 could restore the tumor-killing activity of CD8+ T cells, hence limiting tumor growth and lung metastasis following hepatic IRI. Taken together, these data suggest that IFNα-producing pDCs drive CX3CR1+ MDSC recruitment via hepatocyte IRF1/CX3CL1 signaling and lead to tumor recurrence after hepatectomy in HCC. Targeting pDCs and the IFNα/CX3CL1/CX3CR1 axis could inhibit surgical stress-induced HCC recurrence by attenuating postoperative immunosuppression. SIGNIFICANCE: IFNα secreted by plasmacytoid dendritic cells drives postoperative immunosuppression and early recurrence of hepatocellular carcinoma, providing new biomarkers and therapeutic targets to improve patient outcomes after surgical resection.


Assuntos
Carcinoma Hepatocelular , Células Dendríticas , Interferon-alfa , Neoplasias Hepáticas , Células Supressoras Mieloides , Recidiva Local de Neoplasia , Humanos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Células Dendríticas/metabolismo , Interferon-alfa/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Células Supressoras Mieloides/metabolismo , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia
17.
Nat Prod Res ; 35(12): 1985-1990, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31397172

RESUMO

The chromatographic reinvestigation the methanol extract of Tetraena aegyptia led to the separation of a new flavonoid glycoside, isorhamnetin-3-O-[2```,3```-O-isopropylidene-α-L-rhamnopyranosyl]-(1```→6``)-O-ß-D-glucopyranoside (1), together with two known flavonoids, isorhamnetin (2) and isorhamnetin-3-O-glucoside (3), isolated for the first time from the plant. The new compound was evaluated for the anti-inflammatory activity by using LPS-induce RAW 264.7 cells model. Compound 1 showed significant inhibitory effect on NO release. ELISA assay showed a pronounced effect of 1 on the secretion of cytokines IL-6 and TNF-α, in a dose-dependent manner. Consistent results were obtained by qRT-PCR which revealed that compound 1 markedly reduced the mRNA expression of IL-6 and TNF-α. Together these data, we demonstrated the anti-inflammatory activity of compound 1.


Assuntos
Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Zygophyllaceae/química , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Flavonóis/isolamento & purificação , Flavonóis/farmacologia , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolissacarídeos/toxicidade , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Quercetina/análogos & derivados , Quercetina/isolamento & purificação , Quercetina/farmacologia , Células RAW 264.7 , Fator de Necrose Tumoral alfa
18.
Eur J Cancer Prev ; 30(5): 351-356, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34010241

RESUMO

OBJECTIVE: Hepatocellular carcinoma (HCC) poses a serious threat to human health. ADCY2 gene polymorphisms may be related to HCC susceptibility. Therefore, we investigated whether ADCY2 gene polymorphisms are correlated to the risk of HCC in a Chinese Han population. METHODS: In a case-control study, we examined the associations between single nucleotide polymorphisms (SNPs) in ADCY2 and HCC risk. In 434 HCC cases and 442 healthy controls, we used the Agena MassARRAY platform to select and genotype four tag SNPs in ADCY2. We used logistic regression after adjusting for age and sex to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: The results showed that ADCY2 rs10059539 polymorphism was associated with a reduced susceptibility to HCC in women under the dominant model (TC/TT vs. CC; OR = 0.32; 95% CI = 0.13-0.83; P = 0.018) and the log-additive model (OR = 0.32; 95% CI = 0.13-0.83; P = 0.018). CONCLUSIONS: Our results support the hypothesis that ADCY2 gene polymorphisms influence the genetic susceptibility to HCC.


Assuntos
Adenilil Ciclases/genética , Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/genética , Estudos de Casos e Controles , China/epidemiologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/genética , Polimorfismo de Nucleotídeo Único
19.
Curr Med Sci ; 41(3): 443-453, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34185250

RESUMO

We performed a retrospective analysis to investigate dynamic peri-hematopoietic stem cell transplantation (HSCT) minimal/measurable residual disease (MRD) on outcomes in patients with T-cell acute lymphoblastic leukemia (T-ALL). A total of 271 patients were enrolled and classified into three groups: unchanged negative MRD pre- and post-HSCT group (group A), post-MRD non-increase group (group B), and post-MRD increase group (group C). The patients in group B and group C experienced a higher cumulative incidence of relapse (CIR) (42% vs. 71% vs. 16%, P<0.001) and lower leukemia-free survival (LFS) (46% vs. 21% vs. 70%, P<0.001) and overall survival (OS) (50% vs. 28% vs. 72%, P<0.001) than in group A, but there was no significant difference in non-relapse mortality (NRM) among three groups (14% vs. 12% vs. 8%, P=0.752). Multivariate analysis showed that dynamic peri-HSCT MRD was associated with CIR (HR=2.392, 95% CI, 1.816-3.151, P<0.001), LFS (HR=1.964, 95% CI, 1.546-2.496, P<0.001) and OS (HR=1.731, 95% CI, 1.348-2.222, P<0.001). We also established a risk scoring system based on dynamic peri-HSCT MRD combined with remission status pre-HSCT and onset of chronic graft-versus-host disease (GVHD). This risk scoring system could better distinguish CIR (c=0.730) than that for pre-HSCT MRD (c=0.562), post-HSCT MRD (c=0.616) and pre- and post-MRD dynamics (c=0.648). Our results confirm the outcome predictive value of dynamic peri-HSCT MRD either alone or in combination with other variables for patients with T-ALL.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Neoplasia Residual/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Linfócitos T/metabolismo , Adolescente , Adulto , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos/genética , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Recidiva , Linfócitos T/patologia , Adulto Jovem
20.
Front Pharmacol ; 11: 01261, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33123002

RESUMO

The herb Bolbostemma paniculatum (Maxim) Franquet (Cucurbitaceae family), also known as Tu-Bei-Mu (TBM) in Chinese, has shown curative effects to treat several types of cancer as an adjunctive therapy. Thereby we intend to find its effect on the human hepatocellular carcinoma (HCC) and to understand the pharmacological mechanism behind it. In this study, an integrative serum pharmacology-based approach linking serum pharmacology and bioinformatics prediction was employed. Firstly, we used the serum taken introgastrically from the rats dministered by TBM aqueous bulb extract to culture the HCC cell line BEL-7404 and detect its anti-tumor effects. Secondly, the TBM putative targets were predicted using the ETCM database and known therapeutic targets of NPC were collected from the OMIM database. Then, a TBM-HCC putative targets network was constructed using the DAVID and STRING databases. Thirdly, key gene targets were obtained based on topological analysis and pathway enrichment analysis. The expression of 4 representative key targets were validated by Western blotting. As a result, 36 TBM targets and 26 known therapeutic targets of HCC were identified. These key targets were found to be frequently involved in 13 KEGG pathways and 4 biological processes. The expression of four representative key targets: TP53, CASP3, BCL2 and BAX further supports the suppression of TBM on HCC. In general, our study shows the curative effects of TBM against HCC. By using this integrative approach, we may find novel potential therapeutic targets to suppress HCC using TBM as an adjunctive therapy. And it could also help us understand the mechanism of HCC treatments in response to TBM.

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